数据库出了点问题， Duplicate entry '1' for key 'PRIMARY'

Question

com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry '1' for key 'PRIMARY'

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)

at java.lang.reflect.Constructor.newInstance(Unknown Source)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)

at com.mysql.jdbc.Util.getInstance(Util.java:387)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:932)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3878)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3814)

at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2478)

at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2625)

at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2551)

at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1861)

at com.mysql.jdbc.PreparedStatement.executeUpdateInternal(PreparedStatement.java:2073)

at com.mysql.jdbc.PreparedStatement.executeUpdateInternal(PreparedStatement.java:2009)

at com.mysql.jdbc.PreparedStatement.executeLargeUpdate(PreparedStatement.java:5094)

at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1994)

at org.dao.LoginDao.addInfo(LoginDao.java:73)

at org.servlet.LeaveMessageServlet.doGet(LeaveMessageServlet.java:39)

at org.servlet.LeaveMessageServlet.doPost(LeaveMessageServlet.java:44)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

Answer 1

看这个帖子，帮你问了下朋友http://www.yl1001.com/group_article/5461468980778720.htm?classic_id=4941468982929372#comment_4941468982929372这里只有你的建表语句，并没有你的插入数据语句，所以只能推断你的场景了。messagess表的主键是id，loginss的主键也是id；两个表的id都是自增的，这样的话插入的时候就不要给id赋值，跳过他会自动赋值。报错的原因：表中已经有id为1的记录，你继续往里插新记录了，但是id还是1.解决方法：插入数据跳过id，或者用insert ingore（已有记录不插入新记录）

Answer 2

1L正解，检查下该表的字段是不是有多个主键

Answer 3

select * from table where x= PRIMARY,然后删除或修改重复的条目。